CN-122002516-A - Facilitating coherent joint transmission phase offset calibration using time domain averaging

Abstract

A method for coherent joint transmission (cqt) Phase Offset (PO) calibration with time-domain averaging in a Time Division Duplex (TDD) system is described. The UE may acquire Reference Signal (RS) pairing information indicating a pairing of an Uplink (UL) RS transmitted by the UE during a first measurement period and a Downlink (DL) RS received by the UE from a first Transmission Reception Point (TRP) and a second TRP of a Radio Access Network (RAN) during the first measurement period, and a second pairing of a second UL RS with a DL RS transmitted by the UE during the second measurement period, the DL RS received by the UE from the first TRP and the second TRP during the second measurement period. The UE may determine Channel State Information (CSI) of the DL RS from the second TRP over time relative to the DL RS from the first TRP during the same time. The UE may average a channel phase value of each TRP or a channel phase offset value between TRPs.

Inventors

• F. WALKER
• L. A. Suarez Rivera
• E. Visotsky
• F. Tosato
• R. Kauduro Dias de Paiva

Assignees

• 诺基亚技术有限公司

Dates

Publication Date

20260508

Application Date

20251106

Priority Date

20241108

Claims (20)

1. 1. An apparatus for communication, comprising: At least one processor, and At least one memory including instructions stored thereon, which when executed by the at least one processor, cause the apparatus to at least perform: The reference signal pair information is acquired and, Wherein the reference signal pairing information indicates a first pairing of a first uplink, UL, reference signal to be transmitted by the apparatus during a first measurement period, the first DL reference signal to be received at the apparatus from a first transmission reception point, TRP, of a radio access network, RAN, and a second DL reference signal to be received at the apparatus from a second TRP of the RAN during the first measurement period, And wherein the reference signal pairing information further indicates a second pairing of a second UL reference signal to be transmitted by the apparatus during a second measurement period, a third DL reference signal to be received from the first TRP during the second measurement period at the apparatus, and a fourth DL reference signal to be received from the second TRP during the second measurement period at the apparatus; transmitting the first UL reference signal during the first measurement period, and receiving the first DL reference signal from the first TRP and the second DL reference signal from the second TRP; transmitting the second UL reference signal during the second measurement period, and receiving the third DL reference signal from the first TRP and the fourth DL reference signal from the second TRP; During the first measurement period, performing a first DL measurement of the first DL reference signal and a second DL measurement of the second DL reference signal; performing a third DL measurement of the third DL reference signal and a fourth DL measurement of the fourth DL reference signal during the second measurement period, and Channel state information, CSI, is reported to the RAN, the CSI being derived from at least the first DL measurement, the second DL measurement, the third DL measurement, and the fourth DL measurement.
2. 2. The apparatus of claim 1, wherein the CSI is operable to determine a time-averaged phase offset value between the first TRP and the second TRP for a coherent joint transmission cqt to the apparatus.
3. 3. The apparatus of claim 1 or 2, wherein a time interval between an UL reference signal and a DL reference signal paired with the UL reference signal is less than a threshold.
4. 4. The apparatus of claim 1 or 2, wherein the CSI comprises at least one of: A first channel phase value of a first DL channel between the first TRP and the device derived from the first DL measurement, a second channel phase value of a second DL channel between the second TRP and the device derived from the second DL measurement, a third channel phase value of the first DL channel derived from the third DL measurement, and a fourth channel phase value of the second DL channel derived from the fourth DL measurement, or A first channel phase offset value between the first DL channel and the second DL channel derived from the first DL measurement and the second DL measurement, and a second channel phase offset value between the first DL channel and the second DL channel derived from the third DL measurement and the fourth DL measurement.
5. 5. The apparatus of claim 4, wherein the CSI further comprises measurement pairing information indicating at least one of: pairing of the first and second channel phase values with the first UL reference signal and pairing of the third and fourth channel phase values with the second UL reference signal, or Pairing of the first channel phase offset value with the first UL reference signal and pairing of the second channel phase offset value with the second UL reference signal.
6. 6. The apparatus of claim 1 or 2, wherein the CSI comprises at least one of: A first average channel phase value of a first DL channel between the first TRP and the device derived from at least the first DL measurement and the third DL measurement, and a second average channel phase value of a second DL channel between the second TRP and the device derived from at least the second DL measurement and the fourth DL measurement, or An average channel phase offset value between the first DL channel and the second DL channel derived from at least the first DL measurement, the second DL measurement, the third DL measurement, and the fourth DL measurement.
7. 7. The apparatus according to claim 1 or 2, wherein the instructions are stored on the at least one memory, which when executed by the at least one processor, further cause the apparatus to perform: obtaining average information indicative of at least one of: The number x of measurement periods for the averaging operation; Averaging method for averaging operation, or One or more averaging parameters for the averaging operation.
8. 8. The apparatus of claim 1 or 2, wherein the reference signal pairing information or the average information is obtained via at least one of: Radio resource control, RRC, signaling; One or more medium access control-control elements, MAC-CEs; one or more parameters stored or preconfigured at the device, or One or more technical specifications.
9. 9. The apparatus according to claim 1 or 2, wherein the instructions are stored on the at least one memory, which when executed by the at least one processor, further cause the apparatus to perform: Receiving a trigger from the RAN; In response to the trigger, performing DL measurements including the first DL measurement, the second DL measurement, the third DL measurement, and the fourth DL measurement in x subsequent measurement periods, and reporting the CSI derived from the DL measurements performed during the x measurement periods to the RAN.
10. 10. The apparatus according to claim 1 or 2, wherein the instructions are stored on the at least one memory, which when executed by the at least one processor, further cause the apparatus to perform: Buffering DL measurements including the first DL measurement, the second DL measurement, the third DL measurement, and the fourth DL measurement performed during x most recent measurement periods; Receiving a trigger from the RAN; in response to the trigger, reporting the CSI derived from the DL measurements performed during the x most recent measurement periods to the RAN.
11. 11. The apparatus of claim 9, wherein the trigger comprises at least one of: The reference signal pairing information or The average information.
12. 12. The apparatus of claim 1 or 2, wherein the apparatus comprises or is comprised within a terminal device or a user device.
13. 13. An apparatus for communication, comprising: At least one processor, and At least one memory including instructions stored thereon, which when executed by the at least one processor, cause the apparatus to at least perform: Transmitting configuration information to a terminal device, the configuration information being usable for causing the terminal device to transmit a first uplink, UL, reference signal during a first measurement period and a second UL, reference signal during a second measurement period, and the configuration information being usable for causing the terminal device to receive a first downlink, DL, reference signal from a first transmission reception point, TRP, of a radio access network, RAN, and a second DL reference signal from a second TRP of the RAN, during the first measurement period, and a third DL reference signal from the first TRP and a fourth DL reference signal from the second TRP, Wherein the first DL reference signal and the second DL reference signal are paired with the first UL reference signal and the third DL reference signal and the fourth DL reference signal are paired with the second UL reference signal; obtaining a first UL measurement of the first UL reference signal performed at the first TRP during the first measurement period and a second UL measurement of the first UL reference signal performed at the second TRP during the first measurement period; Acquiring a third UL measurement of the second UL reference signal performed at the first TRP during the second measurement period and a fourth UL measurement of the second UL reference signal performed at the second TRP during the second measurement period, and Receiving channel state information, CSI, from the terminal device, the CSI being derived from at least a first DL measurement of the first DL reference signal and a second DL measurement of the second DL reference signal performed during the first measurement period, and a third DL measurement of the third DL reference signal and a fourth DL measurement of the fourth DL reference signal performed during the second measurement period, and A time-averaged phase offset value for a coherent joint transmission cqt to the terminal device between the second TRP and the first TRP is determined based at least on the first UL measurement, the second UL measurement, the third UL measurement, and the fourth UL measurement, and the CSI received from the terminal device.
14. 14. The apparatus of claim 13, wherein the instructions are stored on the at least one memory, the instructions, when executed by the at least one processor, further cause the apparatus to perform: Based on the time-averaged phase offset value, one or more precoding coefficients used by the second TRP are adjusted for CJT transmissions to the terminal device.
15. 15. The apparatus according to claim 13 or 14, wherein the instructions are stored on the at least one memory, which when executed by the at least one processor, further cause the apparatus to perform: transmitting pairing information to the terminal device, the pairing information indicating the pairing of the first UL reference signal with the first DL reference signal and the second DL reference signal, and the pairing of the second UL reference signal with the third DL reference signal and the fourth DL reference signal.
16. 16. The apparatus of claim 13 or 14, wherein a time interval between an UL reference signal and a DL reference signal paired with the UL reference signal is less than a threshold.
17. 17. The apparatus of claim 13 or 14, wherein the CSI comprises at least one of: A first channel phase value of a first DL channel between the first TRP derived from the first DL measurement and the terminal device, a second channel phase value of a second DL channel between the second TRP derived from the second DL measurement and the terminal device, a third channel phase value of the first DL channel derived from the third DL measurement, and a fourth channel phase value of the second DL channel derived from the fourth DL measurement, or A first channel phase offset value between the first DL channel and the second DL channel derived from the first DL measurement and the second DL measurement, and a second channel phase offset value between the first DL channel and the second DL channel derived from the third DL measurement and the fourth DL measurement.
18. 18. The apparatus of claim 17, wherein the CSI further comprises measurement pairing information indicating at least one of: pairing of the first and second channel phase values with the first UL reference signal and pairing of the third and fourth channel phase values with the second UL reference signal, or Pairing of the first channel phase offset value with the first UL reference signal and pairing of the second channel phase offset value with the second UL reference signal.
19. 19. The apparatus of claim 13 or 14, wherein the CSI comprises at least one of: A first average channel phase value of a first DL channel between the first TRP and the terminal device derived from at least the first DL measurement and the third DL measurement, and a second average channel phase value of a second DL channel between the second TRP and the terminal device derived from at least the second DL measurement and the fourth DL measurement, or An average channel phase offset value between the first DL channel and the second DL channel derived from at least the first DL measurement, the second DL measurement, the third DL measurement, and the fourth DL measurement.
20. 20. The apparatus according to claim 13 or 14, wherein the instructions are stored on the at least one memory, which when executed by the at least one processor, further cause the apparatus to perform: Transmitting average information indicating at least one of the following to the terminal device: The number x of measurement periods for the averaging operation; Averaging method for averaging operation, or One or more averaging parameters for the averaging operation.

Description

Facilitating coherent joint transmission phase offset calibration using time domain averaging Technical Field Example embodiments relate generally to techniques for facilitating coherent joint transmission phase offset calibration and, more particularly, to using time domain averaging to facilitate coherent joint transmission phase offset calibration. Background In modern telecommunication systems, spatial diversity plays a crucial role in both transmission and reception. The techniques may be used to send information over different spatial channels or to distribute information across various channels to increase the transmission rate. At the receiving end, the technique allows the acquisition of multipath signals carrying the same data or different data transmitted over different spatial channels. Phase delay antennas may be used to enable control of the shape of the radiation pattern to form a directional beam, for example for beam forming. These beams, characterized by narrow spread and high gain, are created using a one-or two-dimensional array of antenna elements. Each element has individually controllable gain and phase delays that allow the antenna to steer the beam using variable constructive interference of the wave fronts. Telecommunication standards generally require the use of spatial diversity and beamforming to support multiple-input multiple-output (MIMO) and massive MIMO (MIMO) systems, particularly at the base station. These systems are typically managed by a network to ensure efficient operation. Beamforming communication refers to radio communication using spatially restricted channels or beams of a particular direction with maximum gain. In transmission, beams are formed by weighting the signals applied to each antenna element with phasors represented by amplitudes and phases. These values are chosen to achieve constructive interference along the beam directivity. The antenna elements are typically arranged in a regular array and follow the principle of reciprocity, a similar approach may be used in reception. In spatially controlled communications, such as cellular or beamformed communications, it is important to prevent transmitters from broadcasting outside of their intended areas and to avoid receivers from picking up signals outside of their designated space. This is achieved by controlling the gains of the transmitter and receiver, in beam forming communications by adjusting the magnitude of the phasors used for weighting. In a mobile network or communication system such as a fifth generation (5G) Core Network (CN) or a Radio Access Network (RAN) thereof, signaling, transmission, messages, etc. from user side devices such as terminal devices, user Equipments (UEs), etc. to network side devices such as network nodes, access points, etc. are referred to as Uplink (UL) Transmissions (TX). Further, signaling, transmission, messages, etc. from network-side devices such as network nodes, access points, etc. to user-side devices such as terminal devices, UEs, etc. are referred to as Downlink (DL) TX. Such transmission/signaling may be performed using one or more transmission/communication modes or protocols, such as Frequency Division Duplexing (FDD), time Division Duplexing (TDD), etc. FDD operates by using separate frequency bands for UL and DL communications. This means that data can be transmitted and received simultaneously, making FDD a full duplex system. This approach is generally advantageous in a scenario where UL and DL data rates are symmetric, because FDD allows continuous data flow in both directions. However, FDD generally requires more spectrum because it requires two different frequency bands, which is inefficient in terms of spectrum utilization. TDD, on the other hand, uses the same frequency band for UL and DL, but these transmissions occur at different times. This makes TDD a half duplex system because it alternates between transmitting and receiving data. TDD is more flexible and efficient in terms of spectrum usage, especially in environments where the data rates of UL and DL are asymmetric. TDD may allow operators to dynamically adjust UL and DL capacity based on demand. However, TDD systems require accurate time synchronization to avoid interference, which can complicate deployment in dense environments. Disclosure of Invention The scope of various embodiments of the invention is set forth in the following claims. The embodiments and features (if any) described in this specification that do not fall within the scope of the claims should be construed as examples that facilitate an understanding of the various embodiments of the invention. A method for coherent joint transmission (cqt) Phase Offset (PO) calibration with time-domain averaging in a Time Division Duplex (TDD) system is described. The UE may acquire Reference Signal (RS) pairing information indicating a pairing of an Uplink (UL) RS transmitted by the UE during a first measurement period and a Downlink (